RGB values for UIColor are between 0 and 1 (see the documentation "specified as a value from 0.0 to 1.0")
You need to divide your numbers by 255:
passwordTextField.textColor = UIColor(red: CGFloat(202.0/255.0), green: CGFloat(228.0/255.0), blue: CGFloat(230.0/255.0), alpha: CGFloat(1.0))
Another thing, you don't need to create CGFloats:
passwordTextField.textColor = UIColor(red:202.0/255.0, green:228.0/255.0, blue:230.0/255.0, alpha:1.0)
与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…